1. Field of the Invention
The present invention relates generally to apparatus and methods for moving containers, and more particularly, to an apparatus and method for adapted to move loaded catalyst bins within relatively close quarters.
2. Description of the Relevant Art
In the chemical and petrochemical industry, catalysts are often used to help process hydrocarbons like gas an oil. For example, catalysts are often used to accelerate the “cracking” of heavy gas oil into diesel oils and gasoline and/or kerosene.
Recently, “fracking”, or hydraulic fracturing, has been used to a greater degree to recover natural gas and oil from deep rock formations of spent wellbores. In fracking, a slurry of water, sand and chemicals are injected under high pressure into a wellbore to create small fractures through which gas and oil can escape to the surface. Fracking can make recovery of such resources economically feasible in cases where other known methods would be too costly. Oil and gas recovered via fracking can be processed using fluid catalytic cracking, wherein a heated catalyst breaks down large gas/oil molecules into less-complex molecules. Such catalysts are often supplied in the form of granular “beads”.
After such catalyst beads have been used to process oil/gas mixtures, they are contaminated with hydrocarbon residue, and pose a safety and health risk. Spent hydro-treating catalysts are typically classified by the U.S. Environmental Protection Agency (EPA) as UN 3190, are regulated under dangerous goods class 4.2, and are listed as “hazardous wastes”. Accordingly, used catalyst beads must be disposed of properly.
The most commonly used method is to load such catalyst beads into special catalyst bins or catalyst containers for transportation to a reclamation site. Catalyst bins have been available for many years; examples are found in U.S. Pat. No. 3,318,473 to Jones, et al.; and U.S. Pat. No. 4,662,669 to Erickson, et al. Several manufacturers supply such catalyst bins, including CHEP Technology Pty Limited of Sydney, Australia, and the Flo-Bin Rentals division of CCKX, Inc. of Houston, Tex. Such catalyst bins typically provide approximately 87 cubic feet of storage capacity. These catalyst bins are usually made of heavy gauge steel construction, and while they weigh only approximately 900 pounds when empty, they may weigh as much as 6,000 pounds or more when filled with spent catalyst beads. Such catalyst bins stand upright having a height of approximately 85 inches, and have a base measuring approximately 44 inches by 52 inches. The base of such catalyst bins typically incorporate steel skids having forklift ports for accepting the forks of a forklift. Centered between the forklift ports of the base is a discharge hopper, having a slidegate that can be opened when desired to discharge the contents of the catalyst bin. At the top of the catalyst bin, a drum-lid style fill port is provided for loading catalyst beads into the catalyst bin. Lifting lugs may also be provided at the top of the catalyst bin for using a crane to lift the catalyst bin.
Those skilled in the art should appreciate that, while such catalyst bins are often used to store contaminated catalyst beads, such catalyst bins may also be used to transport other materials, including minerals and even foodstuff. The terms “catalyst bin” and “catalyst container” are used herein to include the above-described catalyst bins whether they are used to store catalyst beads or other materials.
Applicable U.S. regulations regarding transportation of catalyst bins containing spent catalyst beads that have been used for petrochemical refining require a “double-containment” transport method. The catalyst bin serves as a first containment. When such catalyst bins are loaded within a non-refrigerated, enclosed, dry truck trailer, sufficient double-containment is achieved. Accordingly, catalyst bins are often loaded into such truck trailers for transportation within the United States.
As noted above, the base of such catalyst bins typically includes steel skids having forklift entry ports, and a common forklift is often used to elevate and load the catalyst bin onto the rear end of the truck trailer. Typical truck trailers can be used to transport 8-12 such catalyst bins at a time. However, once a catalyst bin has been loaded onto the rear end of the truck trailer by a forklift, final placement of each catalyst bin within the truck trailer is difficult, particularly due to the weight of loaded catalyst bins, and because the person or persons responsible for securing such catalyst bins within the truck trailer are working in relatively close quarters, particularly if one is trying to achieve relatively high packing density of catalyst bins within a truck trailer. Typically, there is not enough room on the truck trailer to efficiently maneuver a forklift in order to place a loaded catalyst bin in a desired final location on the truck trailer. The same issue is faced when the truck trailer has arrived at its destination, e.g., a catalyst reclamation treatment facility, and the catalyst bins must now be removed from the truck trailer.
Apart from hydraulic, gas-powered forklifts, so-called pallet jacks are also known in the art for transporting loads. For example, pallet trucks are available under the “Roughneck” brand from Northern Tool+Equipment Co., Inc. of Burnsville, Minn., and may be capable of lifting loads of approximately 5,500 pounds. However, the width of the spacing between the legs of such pallet trucks is only approximately 14.5 inches, while the fork length is approximately 48 inches. Were one to attempt to insert such a pallet jack into the base of a catalyst bin, the forks of the pallet jack would impact the discharge hopper of the catalyst bin, preventing the forks from being fully inserted, and risking damage to the discharge hopper, with the additional risk of catalyst bead leakage.
There are pallet jacks known in the art which allow for adjustment of the spacing between the fork prongs used to raise a pallet. For example, U.S. Pat. No. 7,641,011 to Fridlington, et al., discloses a pallet jack having width-adjustable fork prongs. However, the mechanism used to increase the spacing between the forks adds to the cost and complexity of the pallet jack. Moreover, even if the forks of a pallet jack could be separated by a sufficient distance to avoid impacting upon the discharge nozzle of a catalyst bin, most pallet jacks lack the lifting capacity to lift a fully-loaded catalyst bin. While some pallet jacks are capable of lifting and moving as much as 8,000 pounds, those pallet jacks are considerably more expensive than those designed to lift 5,500 pound loads.
Also known are pallet jacks having a pair of forks, each of which is adjustable in length; see, for example, U.S. Patent Application Publication No. US 2009/018932 A1 to Meijer, et al. However, even the shortest fork length illustrated by Meijer is not short enough to avoid damage to the discharge nozzle of a catalyst bin.
Incorporating permanently-deployed wheels or rollers within the catalyst bin itself is not a viable solution since such catalyst bins should not easily roll or otherwise move during transport.
Accordingly, it is an object of the present invention to provide an apparatus for efficiently moving and/or placing catalyst bins within tight quarters.
Another object of the present invention is to provide such an apparatus that can easily be operated by a single operator, even when moving fully-loaded catalyst bins.
Still another object of the present invention is to provide such an apparatus that will avoid the risk of damage to the discharge hopper of the catalyst bin.
Yet another object of the present invention is to provide such an apparatus which occupies very little space, but which is capable of supporting the weight of a fully-loaded catalyst bin.
An additional object of the present invention is to provide such an apparatus that facilitates steering of the catalyst bin toward a desired position during movement of the catalyst bin.
A further object of the present invention is to provide such an apparatus that is relatively inexpensive and generally easy to manufacture.
A still further object of the present invention is to provide a novel method of supporting fully-loaded catalyst bins for movement within confined quarters.
These and other objects of the invention will become more apparent to those skilled in the art as the description of the present invention proceeds.